I don't know how many seasons there actually are--what I did notice was that Second Season had an f-ton of story arcs (which I classify as separate from "seasons"). If the First Season has even half as many, it's no wonder I got completely lost in the backstory and lore.
Bakemonogatari has 15 episodes, Nisemonogatari only has 11and Nekomonogatari Black has 4 and that makes up the "First Season" of Monogatari. Kizumonogatari is a Prequal trilogy of movies that cover Araragi's time as a Vampire, and are set just before Bakemonogatari.
Currently watching the 2020 version of Sorcerous Stabber Orphen. The initial reaction I had upon reading the news releases and previews is that this seems to be taking the Sailor Moon Crystal route: a more "faithful" adaptation of the source material and an entirely new cast with the exception of the main character. Halfway in right now...and Orphen indeed is following the Crystal route, complete with all the problems that accompanied that remake. Pacing, for example, if I were to pick the most immediate one.